OBJECTIVES:
Percutaneous coronary intervention (PCI) is a common major medical procedure in the United States. It has previously been estimated there are 600,000–1,000,000 PCIs performed annually, although these results are based on older data. The aim of this study was to accurately estimate the number of PCI procedures and describe potential trends in PCI use during 2010 to 2013.

METHODS:
The National Inpatient Sample (NIS) is the largest publicly available all-payer inpatient healthcare database in the United States, containing a 20% stratified systematic random sample of discharges from all US community hospital discharges. The most recent 4 years of available data, 2010–2013, were used for this analysis. International Classification of Diseases 9th revision (ICD-9) codes were used to identify patients undergoing PCI, as well as to segment high-risk patients based on certain diagnoses. Population sampling weights were used to extrapolate results to national estimates.

RESULTS:
There were 559,219 PCI procedures in 2010 decreasing to 519,100 in 2013, corresponding to a change of -7.2% (p<0.0001). The corresponding rate of PCIs per 10,000 population was 18.08 in 2010 and 16.40 in 2013. Despite the overall decrease in PCI volume, procedures among high-risk patients increased during this time period. PCI procedures among patients with cardiogenic shock increased from 19,932 in 2010 (3.56% of all PCIs) to 22,685 in 2013 (4.37%) and procedures among patients with left ventricular heart failure increased from 40,417 (7.23%) in 2010 to 59,110 (11.39%) in 2013.

CONCLUSIONS:
This study shows that the volume of PCIs in the United States has decreased in recent years, and is significantly lower than previous estimates. Despite the overall decrease in PCI volume, procedures among patients with high-risk characteristics increased during the same time period. This suggests a potential shift in the application of PCI to more severe patients.